This invention relates to a cryogenic liquid expansion turbine.
A cryogenic liquid turbine is well known in the art of cryogenic engineering as, in certain circumstances, an alternative or adjunct to a Joule-Thomson valve.
Even though the turbine operates at a cryogenic temperature, the machine typically has axially disposed components that operate at or above ambient temperatures, particularly a bearing or bearings for supporting a rotary shaft to which the turbine wheel is mounted. In theory, the most thermodynamically efficient cryogenic liquid expansion turbines are those that employ radial fluid inflow. In practice, however, there is a tendency for such effects as undesirable heat flows or formation of a second vapour phase as a result of flashing, or a failure to achieve readily adequate sealing at a bearing between parts at cryogenic temperatures and parts at higher temperatures, to lead to alternative forms of expansion turbine or a Joule-Thomson valve to be chosen instead of a radial inlet liquid expansion turbine.